A gas turbine is configured with a compressor, a combustor, and a turbine. The air inhaled from the air intake is compressed by the compressor to produce compressed air having high temperature and high pressure. In the combustor, fuel is supplied to the compressed air to create combustion, and the combustion gas having high temperature and high pressure drives the turbine, thereby driving a generator connected to the turbine. In this case, the turbine is configured so as that a plurality of turbine nozzles and turbine blades arranged one after the other in a case. The combustion gas drives the blade so as to rotationally drive an output shaft to which the generator is connected. The energy of the combustion gas (flue gas) which drives the turbine is gradually transformed into pressure in an exhaust diffuser so as not to produce loss, and is ejected into atmospheric air.
In the turbine of a gas turbine configured in such manner, the exhaust diffuser is configured so as that the flow area of the exhaust diffuser increases toward the flow direction of flue gas from a turbine exit, or a diffuser inlet, and the flow velocity of the flue gas from which the power is recovered by the turbine can be reduced, thereby recovering pressure.
The gas turbine having such exhaust diffuser includes, for example, a gas turbine described in Patent Literature 1 as listed below.